This invention relates to a security window assembly.

Security window assemblies are used within window openings to provide ventilation and natural light to secure environments while preventing people from entering or exiting or passing objects through the openings. Examples of such environments are prisons and mental health facilities.

WO 2007/110641 describes a security window assembly having a fixed pane, a ventilating part comprising a mesh or screen and a sliding pane which is moveable between positions at which it covers and exposes the ventilating part to prevent or allow passage of air therethrough. When the sliding pane is in the open position, i.e. when the ventilating part is exposed, the ventilating part provides ventilation but prevents the passage of people and/or objects through the window opening due to the presence of the mesh or screen.

As specifically described, the sliding pane is mounted on rails or runners so that it can be pushed or pulled into the open/closed position by an occupant of a room provided with the window assembly.

With this arrangement, there is the possibility that the sliding pane may provide a ligature point from which persons could gain sufficient purchase to purposefully damage the window assembly or to use as a point of attachment from which they could hang themselves.

In addition, the sliding pane can act as a point of weakness insofar as it can be forceably removed from the rails or runners on which it is mounted. An object of the present invention is to provide a security window assembly with a sliding pane with which problems of damage and forceable removal, or use as a ligature point, can be avoided or at least reduced.

According to the present invention there is provided a security window assembly, for a window opening, comprising a frame in which are received sliding and security members, the security member having a ventilating part and a non- ventilating part, the sliding member being slidably moveable relative to the security member between a first position in which it exposes the ventilating part, to allow passage of air therethrough, and a second position in which it covers the ventilating part, wherein the sliding member is disposed outwardly of the security member and is operatively connected to a handle disposed inwardly of the security member, for use in effecting movement of the sliding member between the first and second positions.

Because the sliding member is mounted outwardly of the security member, accessibility of the sliding member to a person situated inwardly of the window assembly can be prevented or limited whereby damage to or removal of the sliding member and use thereof as a ligature point can be avoided or at least reduced. At the same time, due to the provision of the inwardly-located handle which is operatively connected to the sliding member, the sliding member can be moved between its positions by the person situated inwardly of the window assembly. The window assembly may be provided in a room or other space within a secure building whereby references to inward and outward are in relation to that room or space, i.e. internally and externally of that space.

Most preferably, the operative connection between the handle and the sliding member is such that movement of the handle is converted mechanically to sliding movement of the sliding member. The arrangement may be such that all of the sliding movement is derived from mechanical conversion of movement of the handle. Alternatively or additionally, power assistance may be used.

Movement of the handle may be rotational or pivotal, or translational. The handle is preferably mounted on a sub-frame member of the security window assembly. More preferably, the handle is mounted on a horizontal sub-frame member of the security window assembly.

The handle is preferably movably mounted on a surface of the security window assembly, with a gap provided between the handle and the surface. In this case, a deflection member is preferably provided between the surface and the handle to restrict access to said gap.

A gap between the handle and the surface on which the handle is mounted is a potential ligature point as a person could try and use it as an attachment point, or could wedge something into the gap in order to try and damage the security window assembly.

For the avoidance of doubt, the word 'ligature point' is used to refer to a point or surface from which a person could gain sufficient purchase of to purposefully damage the window assembly or to use a point of attachment from which they could potentially hang themselves. The deflection member preferably restricts access to said gap by at least partially covering said gap.

The deflection member preferably at least partially covers a gap between an uppermost edge of the handle and the surface on which the handle is mounted. Such a gap could provide a convenient means of attachment of a rope in that a rope could be slid into the gap and the body of the handle could be used to provide a vertical reaction force to the rope that is sufficient for a person to hang themselves.

More preferably the deflection member entirely covers the gap between the handle and the surface on which it is mounted. The handle may be at least partially housed within the deflection member.

More preferably, the handle may be substantially housed within the deflection member.

The deflection member may be formed integrally with the surface on which it is mounted. For example, the surface on which the handle is mounted may comprise a protrusion or a plurality of protrusions which form the deflection member. As a further example, the handle may be mounted totally or partially within a recess provided in the surface on which it mounted.

The deflection member may be separate to the surface on which the handle is mounted. Where the deflection member is separate to the surface on which the handle is mounted, the deflection member is preferably attached to said surface by fastening elements, e.g. screws, rivets, or by any other suitable means. In this case, the deflection member is preferably attached to said surface by anti tamper fastening elements. Where fastening elements are used, the fastening elements are preferably located behind the handle. This is advantageous insofar as the fastening elements are inaccessible to an occupant of the room and are concealed from view.

Where the deflection member is separate to the surface on which the handle is mounted, the deflection member is preferably mounted on said surface such that no gaps are provided between the deflection member and said surface. This is advantageous in that such gaps would provide potential ligature points.

For the same reason, there is preferably minimal clearance between the deflection member and the handle. Where the handle is mounted on a sub-frame member of the security window assembly, the deflection member is preferably also mounted thereon.

Any edges/corners of the handle are preferably chamfered. This is so as to remove any potentially sharp edges/corners of the handle.

The handle preferably projects from the surface on which it is mounted, inwardly, in a horizontal direction. The handle preferably does not comprise any projections in any other directions. Such projections would provide potential ligature points.

The handle may be tapered and preferably tapers in its direction of projection.

In this case, the handle is preferably trapezoidal in shape. The tapered shape prevents a person from gaining sufficient purchase of the handle to damage it or to use the handle as a point of attachment from which they could potentially hang themselves, as any rope would tend to slide off the handle.

The handle is preferably rotatable. In this case, the handle preferably comprises a rotatable disc. The disc is preferably rotatable about its centre. The disc is preferably attached to or provided with a projection for the application of a turning force. The projection is preferably integrally formed with the disc and the projection and disc preferably form a continuous surface. In this way, no potential ligature points are provided by an interface between the disc and projection or by any apertures provided in the projection or disc. The projection is preferably in one direction only. More preferably, the projection is in a longitudinal direction only, i.e. parallel to the axis of rotation of the handle. If the projection was in another direction then it could have a vertically projecting component for certain orientations of the handle, thereby creating a potential ligature point.

The projection may be tapered and preferably tapers in its direction of projection. In this case, the projection is trapezoidal in shape. The projection provides a means of turning the handle since the projection can be twisted by hand, via gripping of opposed parallel surfaces of the projection. However, the tapered surfaces of the projection prevent a person from gain sufficient purchase of the projection to damage the handle or to use the projection as a point of attachment from which they could potentially hang themselves, as any rope would tend to slide off the projection.

Where the handle is rotatable, the deflection member preferably comprises a planar section which is generally circular in shape and a rim which extends around the periphery of the planar section.

The handle is preferably mounted on the planar section of the deflection member with the handle disc preferably at least partially housed within the rim.

The disc preferably does not protrude beyond the deflection member. If the disc does protrude beyond the deflection member, the section of the disc which protrudes beyond the deflection member is preferably thin in relation to the diameter of the disc. In this way, no ligature point is provided by the disc.

The deflection member preferably further comprises an elongate section which is a hollow, thin walled member of circular cross section which extends from the centre of an outer face (i.e. towards the exterior of the room) of the planar section, in a direction perpendicular to the planar section, and terminates at an open end. The elongate section is preferably integrally formed with the planar section.

The handle disc is preferably of a diameter which is slightly less than that of the rim of the circular section of the deflection member such that the disc may rotate within the rim while minimising aαy gap between then handle and rim. In this way, no ligature point is provided by such a gap.

An outer surface of the rim is preferably inclined to the horizontal. More preferably, it is inclined at any angle of between 30 and 60 degrees to the horizontal. Still more preferably, it is inclined at any angle of 45 degrees to the horizontal. In this way, the rim of the deflection member does not provide a potential ligature point. For example, a rope will not tend to attach to the rim but will tend to slide off its inclined surface.

Where the sliding movement of the sliding member is derived from mechanical conversion of movement of the handle, preferably the operative connection between the handle and the sliding member comprises a mechanical linkage with mechanical advantage.

Where the handle is operated by rotation, the handle may be operatively connected to a pinion which is engageable with a toothed rack that is connected to, or integrally formed with, the sliding member such that rotation of the handle effects movement of the sliding member between the first and second positions. The rack and pinion arrangement acts such that the force exerted on the sliding member is a magnification of the force applied to the handle. This facilitates manual operation of the sliding member. Different gearing arrangements may be used as appropriate. Such a gearing arrangement can be adapted to resist rapid opening or closing of the sliding member by appropriate ratios of gears and due to the inertia of the arrangement.

Where the handle is mounted on a sub-frame member of the security window assembly, the shaft is preferably connected to the handle at one end, passes through an aperture provided in the centre of the deflection member, through a conduit provided in the sub-frame member and is connected at another end to the pinion.

The elongate section of the deflection member preferably passes through the conduit in the sub-frame member and houses the shaft, which passes through the elongate section. The elongate section prevents wear of contact surfaces of the shaft and sub-frame member and provides support to the handle.

The pinion is preferably located between the security member and the sliding member. The toothed rack preferably extends substantially along the length of one side of the sliding member. Even more preferably, the toothed rack extends substantially along an inner side of the sliding member (i.e. the side of the sliding member towards the inside of the room). In this way the rack and pinion arrangement is concealed from view and is inaccessible from either side of the security window assembly.

Preferably the security window assembly comprises some or all of the features of the security window assembly disclosed in WO 2007/ 110641.

The security window assembly is preferably made from standard window assembly components. More preferably the security window assembly is made from conventional uPVC window assembly components. In this case, the width of a gap in a subframe of the security window assembly in which the ventilating part is received is preferably of substantially the same width as a gap in a subframe of the security window assembly in which the fixed pane is received.

All of the features described herein may be combined with any of the above aspects, in any combination. For a better understanding of the invention, and to show how embodiments of the same may be carried into effect, reference will now be made, by way of example, to the accompanying diagrammatic drawings in which:

Figure 1 is a front elevational view of a security window assembly in a closed position according to the present invention; Figure 2 is a rear elevational view of the security window assembly shown in Figure 1. Figure 3 is a partial cross-sectional view of the security window assembly of

Figures 1 and 2, taken along the line A-A.

Figure 4 is a partial cross- sectional view of the security window assembly of Figures 1 and 2, taken along the line B-B.

Figure 5 is a partial cross-sectional view of the security window assembly of

Figures 1 and 2, taken along the line C-C. Figure 6 is a partial cross-sectional view of the security window assembly of

Figures 1 and 2 in an open position, taken along the line E-E. Figure 7 is a partial cross- sectional view of the security window assembly of

Figures 1 and 2 in an open position, taken along the line D-D, Figure 8 is a partial cross-sectional view of a section of the security window assembly of Figures 1 and 2 taken along the line F-F. Figure 9 is an enlarged cross-sectional view of the part of the assembly shown in dotted outline in Figure 8, with some parts shown spaced from their in-use positions, for clarity;

Figure 10 is a side elevational view of a handle and casing shown in Figures 2, 8 and 9.

Figure 11 is a front elevational view of the handle and casing shown in Figure

10.

Figure 12 is a plan view of the handle and casing shown in Figures 10 and 11. Referring to Figures 1 to 12 there is shown a security window assembly 1 comprising a security member 3, and a sliding pane 4.

The security window assembly 1 is of generally similar construction as that disclosed in WO 2007/110641, with the arrangement of the window assembly shown in Figures 2, 3 and 4 of WO 2007/110641 reversed so that the sliding pane 4 is mounted outwardly (i.e. towards the exterior of a room in which the security window assembly is provided) of the security member 3.

The security member 3 comprises a fixed pane 5 and a ventilating part 6 which are each of generally similar construction to a conventional uPVC style double-glazed window pane assembly. The fixed pane 5 and sliding pane 4 comprise sub-frame members 7 having internal reinforcing members of aluminium, steel or any other suitable material. The sub-frame members 7 have sealing parts 32 which engage with outer and inner glass panes of the fixed pane 5, with the panes being separated by spacers 8 of rubber or similar material, so as to maintain an air gap between them to provide thermal and sonic insulation. Thus, the sub-frame members 7, the outer and inner panes of the fixed pane 5 and the spacers 8 form a single sealed unit. The sub-frame members 7 engage with a frame surround, which in turn engages with a wall engaging member 31 which is installed in an exterior wall of a building, Io fix the sealed unit into the wall. The frame surround may also engage with the surround of another similar assembly, or with that of a different type of assembly, such as a sliding pane assembly.

The fixed pane 5 and the sliding pane 4 are mounted within a common frame, with the sliding pane 4 being mounted outwardly of the fixed pane 5, for sliding movement in the direction of the arrow in Figure 1, for example on rails or runners (not shown).

The frame may be a plastics (e.g. uPVC), timber or metallic (e.g. aluminium) construction. The arrangement is such that the when the assembly 1 is installed, the sliding plane 4 lies in a generally vertical plane on an outer side of the assembly, with the fixed plane 5 lying in a generally parallel plane on an inner side of the assembly 1. The frame may be of a generally welded or mechanically jointed construction, as may be the sub-frame members.

The ventilating part 6 is mounted adjacent the fixed pane 5, with the ventilating part 6 and the fixed pane 5 thus forming a single security member on the interior side of the assembly. The ventilating part 6 comprises sub-frame members, within which a panel 9 of wire mesh, perforated metal, lattice, grille or the like, is housed, to allow the passage of light and air but to present a physical barrier to prevent people or objects from passing through (or from being passed through, in the case of weapons or drugs, for example) the opening created when the sliding pane 4 is in the open position. A rotatable handle 10 and a casing 12 are mounted on an inner side (i.e. towards the interior of a room containing the window assembly) of a horizontal sub- frame member 30 of the security window assembly 1.

The handle 10 comprises a disc 13 which is rotatable about its centre and is provided with a projection 14 for the application of a turning force. The projection 14 is integrally formed with the disc 13 to form a continuous surface. In this way, no potential ligature points are provided by an interface between the disc 13 and projection 14 or by any apertures provided in the projection 14 or disc 13.

Corners and edges of the projection 14 are chamfered. This is so as to remove any potentially sharp edges/corners of the handle 10.

The projection 14 has a trapezoidal shape, with a vertical outer face, horizontal upper and lower faces and tapered side faces. The trapezoidal shape prevents a person from gaining sufficient purchase of the handle 10 to damage it or to use the handle as a point of attachment from which they could potentially hang themselves, as any rope would tend to slide off the handle 10.

The casing 12 comprises a circular planar section 15 and an elongate section 16. The elongate section 16 of the casing 12 is a hollow, thin walled member of circular cross section which extends outwardly (i.e. towards the exterior of the room containing the security window assembly) from the centre of an inner face of the planar section 15, in a direction perpendicular to the planar section 15, and terminates at an open end.

The casing 12 is mounted on the sub-frame member 30 by inserting the elongate section 16 within a conduit 17 provided in the sub-frame member 30 such that the planar section 15 is flush with an outer surface of the sub- frame member 30. The planar section 15 is attached to the outer surface of the sub-frame member 30 by screws 18.

A washer 19 is provided between the handle disc 13 and the planar section 15 of the casing 12. The casing 12 is provided with a rim 20 which extends around the periphery of the planar section 15. The rim 20 covers a gap 21 between the handle disc 13 and the planar section 15 of the casing 12. Such a gap could provide a convenient means of attachment of a rope in that a rope could be slid into the gap 21 and the body of the handle 10 could be used to provide a vertical reaction force to the rope that is sufficient for a person to hang themselves.

An outer peripheral surface of the rim 20 is inclined at an angle of 45 degrees to the planar section 15. In this way, the rim 20 does not provide a potential ligature point, For example, a rope will not tend to attach to the rim 20 but will tend to slide off its inclined surface. The diameter of the handle disc 13 is slightly less than that of the rim 20. This allows the handle disc 13 to rotate within the casing 12 while minimising any gap between the handle disc 13 and the rim 20. In this way, no ligature point is provided by such a gap.

The handle 10 is connected to a first end of a shaft 22 by a grub screw. An aperture is provided in the centre of the casing which is coincident with the conduit 17 in the sub-frame member 30. The shaft 22 passes through the aperture, extends through the conduit 17 and the elongate section 16 of the casing 12 and is attached, at a second end, to a pinion 23. The pinion 23 is disposed between the security member 3 and the sliding pane

4. The pinion 23 is attached to the shaft 22 by a grab screw and a washer 24 is mounted on the shaft 22, between the pinion 23 and an outer side of the sub-frame member 30. The washer 24 prevents wear of contact surfaces of the pinion 23 and the casing 12.

The pinion 23 is arranged to engage a toothed rack 25 which is attached to and extends along the length of the inner side of the sliding pane 4. In this way, the rack and pinion arrangement is concealed from view and is inaccessible from either side of the security window assembly 1. With this arrangement, rotation of the handle 10 operates the sliding pane 4 between a 'closed' position in which the ventilating part 6 is fully covered by the sliding pane 4 and an 'open' position in which the ventilating part 6 is fully exposed.

Because the sliding pane 4 is mounted outwardly of the security member 3, accessibility of the sliding pane 4 to a person situated inwardly of the window assembly 1 can be prevented or limited whereby damage to or removal of the sliding member and use thereof as a ligature point can be avoided or at least reduced. At the same time, due to the provision of the inwardly-located handle 10 which is operatively connected to the sliding pane 4, the sliding pane 4 can be moved between its positions by the person situated inwardly of the window assembly 1. No ligature points are provided by the handle or casing due to their shape and configuration.

It is to be understood that the above arrangement has been described by way of example only. Many variations are possible without departing from the scope of the invention.